fix: static typing and final classes

[usu]

Fixes #603

Mark internal classes final

I sticked to the rules outlined by Ocramius in https://ocramius.github.io/blog/when-to-declare-classes-final/

Static typing

Fixes most typing related errors from `phpstan analyze -l 6 src'

• excluding typing of items within arrays (https://phpstan.org/blog/solving-phpstan-no-value-type-specified-in-iterable-type)
• excluding non-typing related errors

[usu]

I also included removal of legacy code in Configuration.php as it was a mix of legacy code and static typing.

With extension phpstan/phpstan-symfony, this now passes Level 6 with one remaining error only (which is obvious, as the CloudFront package is only included as a suggest, not as dependency).

 ------ ---------------------------------------------------------------------
  Line   Configuration.php
 ------ ---------------------------------------------------------------------
  593    Class JeanBeru\HttpCacheCloudFront\Proxy\CloudFront not found.
         💡 Learn more at https://phpstan.org/user-guide/discovering-symbols
 ------ ---------------------------------------------------------------------

[dbu]

thanks a lot for this one! just one small question.

we should add a ci step for phpstan similar to FOSHttpCache https://github.com/FriendsOfSymfony/FOSHttpCache/blob/3.x/.github/workflows/static.yml

(where we could require the optional dependency, or alternatively tell phpstan about its possible existence)

[usu]

we should add a ci step for phpstan similar to FOSHttpCache https://github.com/FriendsOfSymfony/FOSHttpCache/blob/3.x/.github/workflows/static.yml

(where we could require the optional dependency, or alternatively tell phpstan about its possible existence)

Yeah, fully agree. I can make a seperate PR for this.

[dbu]

thanks a lot!